Add fallback behavior if the last used profile cannot initialize

chrome/browser/profiles/profiles_state.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/profiles/profiles_state.h"
 
 #include <stddef.h>
 
 #include "base/files/file_path.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 197 matching lines @@
   const base::FilePath& active_profile_path =
       profile_manager->GetLastUsedProfileDir(profile_manager->user_data_dir());
   const base::FilePath& guest_path = ProfileManager::GetGuestProfilePath();
   if (active_profile_path == guest_path)
     return true;
 
   ProfileAttributesEntry* entry;
   bool has_entry =
       g_browser_process->profile_manager()->GetProfileAttributesStorage().
           GetProfileAttributesWithPath(active_profile_path, &entry);
-  DCHECK(has_entry);
 
-  if (!entry->IsSigninRequired())
+  // |has_entry| is possible to be false if a profile is specified in the
+  // --profile-directory switch.

[Peter Kasting, 2016/07/01 00:53:23]

Nit: "|has_entry| may be false when the user specified a profile on the command
line."

[WC Leung, 2016/07/07 17:01:53]

Done.

+  if (has_entry && !entry->IsSigninRequired())
     return false;
 
   SetLastUsedProfile(guest_path.BaseName().MaybeAsASCII());
 
   return true;
 }
 
 void RemoveBrowsingDataForProfile(const base::FilePath& profile_path) {
   // The BrowsingDataRemover relies on the ResourceDispatcherHost, which is
   // null in unit tests.
@@ skipping 39 matching lines @@
     if (!entry->IsSigninRequired() &&
         !entry->IsChild() &&
         !entry->IsLegacySupervised()) {
       return false;
     }
   }
   return all_profiles_locked;
 }
 
 }  // namespace profiles